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Downpipe Installation (Elbowed)

32493 Views 43 Replies 15 Participants Last post by  RPW00Mirage
Ok so here we go. Strap the fuck in because this is going to be one LONG ass Post. I spent this past weekend in my garage installing a downpipe (complete with the elbow) on the VT. 35,000 foot overview is this… Although this is technically a “bolt on” mod; it is not a job I would attempt if I wasn’t fairly well outfitted with tools and had spent a lot of time wrenching in some capacity or another over the last 15 years. If you aren’t a badass with a wrench, you better at least have balls the size of watermelons.

This build started late Friday night and ended Sunday morning. Actually wrench time is probably only about 4 hours, maybe 5. This is assuming you have everything you need to start with.

DISCLAIMER - If you break your shit because you read this thread and suddenly decide you can hang. YOUR FAULT. This information is meant to be supplemental and, dare I say, entertaining! I am not responsible for your vehicle or your own personal health. So use this info how you wish, but if you are worried about any part of this modification, pay a professional and tell em TyBardy said your balls weren’t quite watermelon enough…

Quick Pics — Here is the part I put in next to the part I took out. The Xe TXE is an amazing piece of equipment and if/when they get their downpipe going, those who get in on that are going to be super happy.

Auto part Pipe Automotive engine part

Automotive exhaust Auto part Catalytic converter Muffler

Let’s start with the tools needed. I would take a picture but I seriously used a pretty wide array of tools. Essentially I used all three of my ratchets (1/4”, 3/8”, and ½” drive) at one point or another. I also used a pretty extensive array of extensions. Yes, you NEED various extensions to do this project. Honestly, I think I used three of four of varying length from 2” to 6”. The sockets you will need at various points in your build are 8mm, 10mm, 12mm, 14mm, 17mm, 18mm, and 19mm. You will also need either a 20mm O2 sensor socket or a 20mm wrench. I actually have neither so made do with my large crescent wrench (more on this later). I would also recommend having a flathead screw driver handy as well as some needle nose pliers to unhook a few clips along the way. A also needed my cheater bar (to break loose the lower engine mount). Lastly, you will be using good old fashion wrenches as well. In one case, it was the ONLY tool I was able to use. So have your metric wrenches available in the sized noted above. Most of these tools are used for the tear down preparation and not the Downpipe itself.

- ¼”, 3/8”, and ½” drive socket wrenches
- 8mm, 10mm, 12mm, 14mm, 17mm, 18mm, and 19mm sockets (in various drive configurations)
- All the same sizes above in standard wrenches.
- 20mm wrench OR O2 Sensor wrench OR large crescent wrench
- Needle nose pliers
- Various socket extensions between 2” and 6” long.

NOTE ON TOOLS — as of right now, based on the way I did my build, I absolutely NEEDED a 12mm super stubby open face wrench for one bolt. Nothing else would work and if I didn’t have this I would have had to go buy one. I will say that if you buy the right hardware, there is another method (more on that later). This may not be the case if you have an 845, Tork, SXTH, or some other DP.
Let’s talk about materials — If you are like me and buy the supremely bad ass Xe TXE, you will need to marry it up to a downpipe that does NOT have the elbow already. I used the Pierce Motorsports Street Downpipe. Because I have a 2016, the elbow is integrated into the catalytic converter. What this means is, I do not have the nuts and springs needed from my OEM setup to complete the build with what is supplied by Xe. Their part was designed to be installed prior to the 2016 model. But, I found a solution. ACE hardware has the compression springs I needed and I married those up to some washers and nuts and everything fit like a condom!

Screw Auto part Suspension Coil spring Suspension part

You will also need to get some gaskets. I only got one (the turbo gasket) as I hadn’t thought about the other (DP to Catback gasket), fuck it though right, reuse the old one... YOLO!?!?!? I will replace it later when I drill out the second cat. You will want to get a fresh gasket to go between the elbow and the turbo for sure. The OEM Turbo stud nuts CAN NOT BE REUSED with the TXE that I have. With that being said, I am going to run on the assumption that other DP’s have the same issue. If your DP can be installed with the OEM nuts, I feel bad for you son because the reason my shit needs new hardware is because the TXE is massively oversized for better air flow thus making it an all-around Bad Mother Fucker.

- OEM Turbo Gasket Part number — 28282 2B700 (Trust me on this!!)
- Nut Specs — M8-1.25 (go with ARP 12 point because they shrink from 12mm to 10mm)
- Springs — sorry no part number as I lost the receipt. ACE Hardware has what is needed though.
- Also go get Permatex Fast Break Penetrating Oil, seriously, GET THIS STUFF!! I didn’t break studs and this was the primary lube I used…. I also hear Kroil is awesome. PB Blaster isn’t going to be your best option here but I did use PB blaster in a supplementary fashion with my Permatex.
- I didn’t replace the gasket between the downpipe and the catback. I probably will soon though. Just forgot all about it. So thus, I don’t have the part number.
- In my case (if you have a PMS Street DP you NEED this) O2 Sensor harness extensions. I still haven’t ordered mine so I don’t know the part number. Edits to come.

Drink Red bull Floor Energy drink Alcohol

OK!!!!!! You ready for the actually build out?? Fuck no you aren’t, I wasn’t, but let’s do that shit anyway :crazy:
I highly recommend allotting 48 hours for this build and here is why. Those Turbo Nuts/studs need to soak and soak and soak some more if you have any hope of not breaking a turbo stud. The nightmare of this project (from what I hear) is that if you snap a turbo stud, the entire exhaust manifold must be removed, drilled, and tapped to fix the issue. AINT NOBODY GOT TIME FOR THAT! Not only did I not break any of my suds, but it didn’t require a ton of torque to remove the nuts. (Thanks again Permatex)
PREP — you NEED to remove the following. I am not going to go into details on this as I assume you know how. If you don’t know how to remove these parts, then stop what you are doing and pay a professional because… no watermelon balls.

- Remove the entire intake assembly. Tube, airbox if you have one, etc (You do not need to remove the rear charge pipe that is connected directly to the turbo, just the intake tube and box)
- Remove the battery completely
- Remove the battery tray completely.
- Disconnect (but don’t remove) the ECU behind the batter (this make it easy to maneuver).
- If you have a strut bar, it’s got to go so remove that shit.
- If you have OEM Hot Pipe (or an ORHP for that matter), remove it. If you have intercooler, probably still removing the hot side pipe. (You need all the room you can get, which still won’t be much)
- Remove the lower engine mount (if you’ve never done this, I had to use my cheater bar)
- I didn’t, but if I had it to do again, remove the front bumper fascia. You’ll be rubbing all over this the entire time and it would be easier to just have it out of the way (again, not needed though).
- Remove the heat shield that is directly connected to the Catalytic converter (don’t worry about the heat shield on the elbow itself, I’ll explain why later)

Once all that is removed… It’s downpipe time baby!

PSYCH! At this point, you really need to be (almost) done working for many many hours because this is the point where you can access all three turbo studs to get them SOAKED in penetrating oil. I started Friday night and at that time I was able to hit all three studs/nuts with Permatex Fast Break. From underneath the car I was able to hit two of the three nuts. With everything removed you can easily spot the bottom stud and then fairly easily spot the top-front stud. Hit both from underneath. Either have eye protection on or get your head out of the way… it drips and you do NOT want that shit in your eyes, Seriously, it might warranty a trip to urgent care. The third is harder to get to as you have to access from above and kind of get the can of lube in and get the sprayer tube pointed in the general direction of the nut and spray away until it’s well coated. After that, go to sleep. I let this sit overnight.

the bottom most nut (the other top-front nut is easily seen from below but not in this photo. It is approximatly where I drew this circle)

Auto part Engine Fuel line Pipe Vehicle

this is the angle you need to take to access the top...

Auto part Engine Vehicle Fuel line Car

Auto part Fuel line Pipe Suspension Tire

Saturday morning I repeated the soaking process outlined above. Again with Permatex and walked away. A few hours later I hit all three with PB Blaster (I have it so I figure I would use my entire arsenal). After another couple hours of PB soaking I then mixed up some ATF Fluid and Acetone. I’ve read this works but I could only get this on two of the three studs as I have no way to really apply it. So about 28 or 20 hours after my first soak, you’re ready to break free those turbo nuts.

NOTE — If you have a 2016, you do NOT need to remove the heat shield that is attached to the elbow. Fact is, you can’t and I spun my wheels trying to figure this out only to learn that it stays attached for this process. The shield itself has a cutout to allow you to access all the nuts. I am not sure about the older models, but I think this rule applies across the board.

I started with the bottom stud using a 12mm open face wrench (I also hit it with a fresh spritz of Permatex immediately prior to wrenching). Without a lot of jerking and yanking I applied smooth and even pressure and the nut broke free. I slowly backed the nut off the stud(make sure you do this slow and steady as I have read that people are breaking the stud even as the nut was half way removed). SUCCUSS :nerd:..… for a second here I had a plumpy because the project seemed more doable now. I moved to the other nut that can be seen from below (top-front). This one had to be done with the 3/8” drive 12mm socket and short extension. Same principals as before… and… SUCCESS!! FUCK YES!! My plumpy is almost full wood now! :saint:

Now the third bolt (top-rear). This one is the mother fucker all the way around. Comes off easier than it goes back on though (you’ll read more later). It can only be gotten to from above as you see here. This is the angle you need to take. Notice the socket here is already attached to the nut.

Auto part Engine Vehicle Car Fuel line

NOTE - this is the same way you need to spray the nuts down with your lube.

With smooth and even pressure and slow movement, I got this third bitch out!! :cool2: At this point… I literally washed my hands and poured three fingers of Vondka because this was the part I was most terrified about! NOTHING BROKE SO.... FUCK YES

Back to businuess
After you’ve gotten the three nuts removed you simply need to remove the two nuts connecting the DP to the Catback. A quick splash of Permatex and these came off no problem. The DP hanger is a pain in the ass but self explanatory, just really tight on there.

But we forgot something didn’t we?!?! MOTHER FUCKING O2 SENSORS!! YUP, at least I forgot about these during the process and spent about 30 minutes trying to figure out how to remove them. Then it hit me! hahaha

If I did this job 100 time, I would do it the same 100 times. Up top, simply disconnect both O2 sensor harnesses. The harness connectors are located right behind the motor on the top.

There are also four clips between the two harnesses holding the wires in place. This is where you need your needle nose pliers to get those clips free without breaking them.
Once you’ve completely disconnected the harnesses from the car, simply pull the downpipe out from the rear with the O2 Sensors still connected to the DP.

EASY PEASY LEMON SQEEZY …. Or however that shit goes.

I guess now is a good time to tell you a couple things. One — you’ve done the hard parts in my opinion. Two, the downstream O2 sensor was badly seized into place on my OEM setup. With many many applications of permatex, PB Blaster, and 50/50 mix both inside and out I was finally able to get it free (in my case, this happened long after I got the car put back together).

I believe the easiest way to go is to install the O2 sensors into your new DP prior to putting the DP into your car. In my case, the O2 sensors move so far that I need to buy some extension harnesses. But that is not going to be the case in everyone’s scenario based on the DP you buy. The PMS Street DP simply relocated the sensor further away.

Now that your new downpipe has the sensors installed, remove the old gasket from the turbo and put the new one up in place (on the turbo). You are ready to slide your new part into place (slide in the same way you took OEM out obviously). Once in, CAREFULLY slide the elbow over the turbo studs (you don’t want to round off any threads).

If you bought the ARP 12 point hardware (and you did… didn’t you??? Because life is so much better if you did this!!) than this next step is pretty straight forward… however, it might have been the most challenging part of my whole project for a number of reasons.

And here are those reasons! Let’s talk about the absolutely infuriating little fucker that is the Top-Rear nut/stud. Due to the over sized nature of the TXE, it is virtually impossible to get a socket onto the nut as the socket-wall is too thick for the space between the nut and the elbow. I am not sure how this applies to the 845, Tork, SXTH, et. al. but the OEM elbow has divots at all three hardware locations to make installation easier. See the photo in the next post (I've reached my max number of photos for one post) or the OEM setup and why it’s easier to work with.

So, the only way I was able to thread the top-rear nut (after trying a number of methods over the course of what felt like a fucking eternity) was to START with this nut. What you do is pull the elbow off the turbo so that I could get my hand up between the eblow and turbo. Then, gently push the eblow just close enough so I could get the nut to bite and hand thread a little bit of that thing.

This was a very short way of writing this… to say that this process alone probably took an hour of cursing, swearing, smoking, drinking, under the car, over the car, back under the car, back over the car… fuck fuck fuck… it was a pain.

That was my successful path so I would start there if I were you. The other two threaded on easily enough and I used my socket to tighten them down (mind you I still have not tightened that top nut… its simply threaded a little bit as mentioned). After tightening the other two nuts, the ONLY way I could get that third nut tightened down was to access it from above with a stubby open face wrench. I had to bend the thin heat shield a bit to get to it (I just bent it back when I was done, no biggie). Took me forever to get this third nut tight as I could only turn it about 1/8 turn at a time. Again... this shit felt like an eternity!!!
Welp! At this point, simply attach the lower DP to the catback using the hardware that comes with your DP. If you’re like me, you reused the gasket that was already there. But for between $10 and $20 you can get a new gasket from the dealer.

Before you put everything back together, I’d suggest taking a second to stand back and give yourself a greasy pat on the back because you just performed a pretty intense wrench job for a bolt on modification.
Put everything back on and you are freaking done dude! No, seriously (and only after reading 3,000 words on a forum no less)

So — A few thoughts and notes about the project. I was examining the OEM nuts and noticed something interesting which I think is lending itself to the high rate of turbo studs breaking. The OEM nuts are actually crimped. See the photos. So even if you can reuse these… don’t. Get new nuts. And use lots of lube (Photo of these goofy SOBs in the next post)

Another thing, if you go to the dealer and ask them for the gasket between the turbo and the elbow and don’t specifically give them the part number I told you … they WILL give you the wrong shit. They will give you 28286 2B700 which is simply incorrect.

Lastly, I had my entire DP ceramic coated locally for $60. I would recommend everyone do this. You are spending a lot of money on this very nice part and you are SAVING a lot of money buy doing the wrenching yourself, get it coated and lower your engine temps will ya. Plus it looks bas ass and isn’t that half the reason we do this shit (STFU and don’t judge me)

And certainly not least, I would now like to Thank E9C900A and Xenon Element. E9 was extraordinarily helpful through this process not only with the TXE that I got from Xe but with a ton of info, tips, and taking all my questions through the process, even though many of them were redundant. His personal assistance as well as his product support page were immensely helpful. My success here was really only ensured due to his contribution to my build. Although this is my write up, there is a LOT of information above that I would not have without him and the rest of the Xe staff.

Special thanks to trdtoy for his information. Robo for some of the early data he gave me on DP swaps. And VOODOOIdol (who I don’t think is around anymore).

If anyone has questions or thinks I missed something let me know and I will edit it into the original post.


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Here is the inside of the OEM elbow to show the divits that make the nuts easier to remove and install.
Auto part Automotive exhaust

Picture of the OEM nuts showing the crimped ends
Circle Ceiling Button Rim

Screw Auto part

Let me know what else you need -
Auto part Engine Vehicle Automotive engine part Car
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Thanks for pretty much confirming that the OEM downpipe is never coming off my car. A sad but realistic truth.
hahahaha..... bring it to my house. I'm game to do this shit again! Fun as hell
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Thank you for posting those pics. I'm going to show that to my installer this Friday so he can see what to look for.
Glad I could help

Where you at fam. I'm on my way lol

Sent from my SM-N920T using Tapatalk
about 6 hours away hommie
Very nice! I need to finish our downpipe install instructions lol
Still haven't bought any 6EE products which is kind of a shame becasue from what I can tell, you make a lot of top shelf items! But I've heard that you also have some of the most comprehensive installation instructions in the game. I wish my buddy came over when I did mine becuase I intended to video a lot of this install. Ended up flying solo and thus... less coverage.

I dig the write up! Nicely done! Make me want to tackle a DP.
After all is said and done, it was a fun project. Soak Soak Soak Soak Soak those turbo studs in something better than WD-40 or PB Blaster.
Soak soak soak soak soak them bolts in something better than PB Blaster. I actually used a combination of Permatex Fast Break and PB Blaster. I soaked the ever loving Shit out of those bolts with multiple applications over the course of about 18 hours. I did not use heat. The only other thing I'll say, no jerking motion. Smooth even pressure.
I've run into a number of people who swear by kroil.
Ok... here is an update after a number of weeks and a bevy of issues resolved. I could not find a harness extension and I didn't want to solder an extension so I cut back the tape on the motor harness and it gave me the slack I needed to plug the O2 sensors in. Once I plugged them in, almost all of my hesitation issues went away that I've been talking about. Power was increased already, but after the O2 sensors were fixed it was so much better. Love this mod!

That said, I still have a CEL... but this time I am throwing P0139. From what I am reading this is directly related to the 90* O2 extension I am using. I am going to try removing the spacer nut and getting it closer. If that doesn;t work I am going to get a "better" O2 extension as I bought a cheaper version that wasn't as proven as other parts I've seen.
Seriously... All hail the TXE. The world will be a better place if and when you get the XE DP going as I essentially have it in its infancy form and I love it like Eddie Murphy loves fat suits.

This CEL situation is how pissing me off sometimes fierce. Going to order that bung when I get home today and hope to god it fixes the issue because the C1555 will not go away.
I pulled it out completely and will run the car a few times to see what happens. I'm not hitting the panic button until I get the new bung extension, it's just an annoyance because the car is running so good now I can't complain at all about the butt dyno
If you get a top quality penetrating oil and soak overnight with a couple of applications the entire job will go without any problems at all. All things considered... The job isn't extremely difficult if you know how to work on cars... its just a bit time consuming and requires more care than average. The limited access makes in annoying. My experience was made more difficult becuase of the Xe TXE itself. The elbow is larger than any of it's competators and thus it leaves almost no space to work with (but flows like a champ).

If you are mechnically inclined and invest in a good oil... you're fine. Go mix yourself some 50% ATF and 50% acetone and get a spray bottle. that shit is like magic!!
I've met and/or talked with a number of people who have done this job without issue and every single time had the exact same thing... Soaked the studs multiple times over the course of many hours and everything went smooth.
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Where did all the images go??????????????????? Kinda useless read without them
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